First of all, I'm sorry for your desk to house so much hardware around
You should be able to connect your printer for basic device recognition and driver install, if not then running windows update should get the drivers, even if limited ones. This for both printers.
About the scanner, you do know that you can install Vista drivers on Windows 7, right?
Try here: http://www.usa.canon.com/cusa/support/consumer/scanners/canoscan_series/canoscan_9900f#DriversAndSoftware
And perhaps this would enable you to install the G85 on xp (assuming it's the regular and the non-
xi model):
http://h20000.www2.hp.com/bizsupport/TechSupport/SoftwareDescription.jsp?lang=en&cc=us&prodTypeId=18972&prodSeriesId=30374&prodNameId=19543&swEnvOID=228&swLang=8&mode=2&taskId=135&swItem=oj-6106-3
The procedure for installing on Vista/7 is similar to the PSC 1210.